:root{color:#1d1d1f;background:#eef1f4;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,SF Pro Display,Segoe UI,sans-serif;font-synthesis:none;text-rendering:optimizeLegibility}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;min-width:320px}button{border:0;color:inherit;cursor:pointer;font:inherit}h1,h2,h3,p{margin-top:0}.app-shell{margin:0 auto;max-width:1440px;min-height:100vh;padding:18px}.topbar{align-items:center;-webkit-backdrop-filter:blur(28px);backdrop-filter:blur(28px);background:#ffffffb8;border:1px solid rgb(255 255 255 / .72);border-radius:8px;box-shadow:0 18px 50px #1f23291c;display:flex;justify-content:space-between;margin-bottom:16px;min-height:86px;padding:16px 18px;position:sticky;top:12px;z-index:10}.eyebrow{color:#68717d;font-size:.76rem;font-weight:800;letter-spacing:0;margin-bottom:4px;text-transform:uppercase}h1{font-size:clamp(2.2rem,5vw,4.4rem);line-height:.95;margin-bottom:0}.page-kicker{color:#4e5b68;font-size:1rem;font-weight:850;margin:8px 0 0}h2{font-size:clamp(1.4rem,2.4vw,2.2rem);line-height:1.08;margin-bottom:0}.topbar-actions{align-items:center;display:flex;gap:10px}.progress-pill{align-items:baseline;background:#1d1d1f;border-radius:999px;color:#fff;display:inline-flex;font-weight:850;gap:4px;min-width:82px;padding:10px 14px}.progress-pill small{color:#ffffffb8;font-weight:700}.ghost-button,.icon-button{background:#f7f8fa;border:1px solid #d8dde3;border-radius:8px;font-weight:800;min-height:44px;padding:10px 14px}.ghost-button:hover,.icon-button:hover{background:#eceff3}.workspace{align-items:start;display:grid;gap:16px;grid-template-columns:174px minmax(0,1fr)}.workspace-index{grid-template-columns:minmax(0,1fr)}.side-nav,.panel{-webkit-backdrop-filter:blur(22px);backdrop-filter:blur(22px);background:#ffffffc7;border:1px solid rgb(255 255 255 / .88);border-radius:8px;box-shadow:0 16px 46px #1f232917}.side-nav{display:grid;gap:6px;padding:10px;position:sticky;top:116px}.side-nav button{align-items:center;background:transparent;border-radius:7px;color:#303846;display:flex;font-size:.94rem;font-weight:800;gap:8px;justify-content:flex-start;min-height:42px;padding:12px;text-align:left;width:100%}.side-nav button span{align-items:center;background:#e8edf2;border-radius:999px;color:#536171;display:inline-flex;flex:0 0 auto;font-size:.78rem;font-weight:900;height:24px;justify-content:center;width:24px}.side-nav button:hover{background:#edf1f6}.side-nav button.active{background:#1d1d1f;color:#fff}.side-nav button.active span{background:#ffffff2e;color:#fff}.content-stack{display:grid;gap:16px;min-width:0}.panel{min-height:calc(100vh - 142px);padding:clamp(16px,2vw,24px);scroll-margin-top:116px}.page-actions{align-items:center;background:#ffffffc7;border:1px solid rgb(255 255 255 / .88);border-radius:8px;box-shadow:0 16px 46px #1f232912;display:flex;gap:12px;justify-content:space-between;padding:12px}.page-actions button{background:#1d1d1f;border-radius:8px;color:#fff;font-weight:850;min-height:44px;min-width:108px;padding:10px 16px}.page-actions button:disabled{background:#dfe4ea;color:#87929f;cursor:not-allowed}.page-actions span{color:#596575;font-weight:900}.section-header{align-items:end;border-bottom:1px solid #e3e7ec;display:flex;gap:14px;justify-content:space-between;margin-bottom:18px;padding-bottom:14px}.section-header>span{background:#eef3f7;border:1px solid #dce2e8;border-radius:999px;color:#4f5c69;font-size:.86rem;font-weight:800;padding:8px 11px;white-space:nowrap}.book-stats{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:18px}.book-stats span{background:#1d1d1f;border-radius:999px;color:#fff;font-weight:850;padding:8px 12px}.book-choice-grid{display:grid;gap:14px;grid-template-columns:repeat(auto-fit,minmax(260px,1fr))}.book-choice-card{background:#fff;border:1px solid #dce2e8;border-radius:8px;display:grid;gap:10px;min-height:168px;padding:18px;text-align:left}.book-choice-card:hover{background:#f0f5f8;border-color:#c8d1db}.book-choice-card span{color:#66717e;font-size:.82rem;font-weight:900;text-transform:uppercase}.book-choice-card strong{color:#1d1d1f;font-size:1.7rem;line-height:1.08}.book-choice-card small{color:#596575;font-weight:800}.unit-grid{display:grid;gap:16px}.unit-block{background:#f8fafc;border:1px solid #e1e6eb;border-radius:8px;padding:14px}.unit-heading{align-items:end;display:flex;gap:12px;justify-content:space-between;margin-bottom:12px}.unit-heading h3{font-size:1.05rem;margin:0}.chapter-grid{display:grid;gap:10px;grid-template-columns:repeat(2,minmax(0,1fr))}.chapter-grid button{background:#fff;border:1px solid #dce2e8;border-radius:8px;display:grid;gap:6px;min-height:124px;padding:12px;text-align:left}.chapter-grid button:hover{background:#f0f5f8}.chapter-grid button.active{border-color:#1d1d1f;box-shadow:inset 0 0 0 1px #1d1d1f}.chapter-grid span{color:#66717e;font-size:.78rem;font-weight:900;text-transform:uppercase}.chapter-grid strong{color:#1d1d1f;font-size:1rem;line-height:1.2}.chapter-grid small{color:#66717e;line-height:1.35}.chapter-title{color:#596575;font-size:1.05rem;font-weight:800;margin-bottom:16px}.pretest-list{display:grid;gap:10px}.pretest-row{align-items:center;background:#f8fafc;border:1px solid #e1e6eb;border-radius:8px;display:grid;gap:12px;grid-template-columns:210px minmax(0,1fr);min-height:72px;padding:10px}.question-stem{align-items:center;display:flex;gap:10px;min-width:0}.question-stem span,.word-card-top span,.drop-number{align-items:center;background:#e8edf2;border-radius:999px;color:#4f5c69;display:inline-flex;flex:0 0 auto;font-size:.84rem;font-weight:850;height:32px;justify-content:center;min-width:32px;padding:0 9px}.question-stem strong{font-size:1.05rem;overflow-wrap:anywhere}.segmented-options,.card-options{display:grid;gap:6px;grid-template-columns:repeat(3,minmax(0,1fr))}.segmented-options button,.card-options button{align-items:center;background:#fff;border:1px solid #dce2e8;border-radius:7px;display:flex;font-weight:750;gap:8px;justify-content:flex-start;min-height:48px;overflow-wrap:anywhere;padding:9px 10px;text-align:left}.segmented-options button span,.card-options button span{align-items:center;background:#edf1f5;border-radius:999px;color:#536171;display:inline-flex;flex:0 0 auto;font-size:.78rem;font-weight:900;height:24px;justify-content:center;text-transform:uppercase;width:24px}.segmented-options button:hover,.card-options button:hover,.word-bank button:hover{background:#f0f5f8}.segmented-options button.selected,.card-options button.selected{border-color:#8ca0b4;box-shadow:inset 0 0 0 1px #8ca0b4}.is-correct{background:#edf8f0;border-color:#83c697}.is-wrong{background:#fff0ef;border-color:#e58b85}.is-correct .selected{background:#d9f1df;border-color:#58b774}.is-wrong .selected{background:#ffe0de;border-color:#d9615c}.word-card-grid{display:grid;gap:14px;grid-template-columns:repeat(2,minmax(0,1fr))}.word-card{background:#f8fafc;border:1px solid #e1e6eb;border-radius:8px;display:grid;gap:14px;min-height:360px;padding:16px}.word-card-top{align-items:start;display:flex;gap:12px}.word-card h3{font-size:clamp(2rem,4vw,3.4rem);line-height:.95;margin-bottom:8px}.word-meta{color:#64717e;font-weight:800;margin-bottom:8px}.phonics-row{align-items:center;display:flex;flex-wrap:wrap;gap:6px}.phonics-row span{background:transparent;border-radius:0;color:#6a7480;display:inline;font-size:.78rem;font-weight:900;height:auto;min-width:0;padding:0;text-transform:uppercase}.phonics-row b{background:#eaf0f5;border:1px solid #d7e0e8;border-radius:999px;color:#334252;font-size:.9rem;line-height:1;padding:7px 10px}.examples{display:grid;gap:8px}.examples p{background:#ffffffb8;border-left:4px solid #c9d3dd;border-radius:7px;line-height:1.45;margin-bottom:0;padding:10px 12px}.word-bank{background:#f7f9fb;border:1px solid #dce3ea;border-radius:8px;display:flex;flex-wrap:wrap;gap:8px;margin-bottom:16px;min-height:70px;padding:12px}.word-bank button{background:#fff;border:1px solid #d6dee6;border-radius:999px;box-shadow:0 8px 22px #1f23290f;font-weight:850;min-height:44px;padding:9px 14px;touch-action:none}.word-bank button.selected{background:#1d1d1f;border-color:#1d1d1f;color:#fff}.drop-list{display:grid;gap:10px}.drop-row{align-items:start;background:#f8fafc;border:1px solid #e1e6eb;border-radius:8px;display:grid;gap:10px;grid-template-columns:auto minmax(0,1fr);min-height:72px;padding:12px}.drop-row p{font-size:1.04rem;line-height:1.8;margin-bottom:0}.drop-blank{background:#fff;border:1px dashed #9aa8b7;border-radius:7px;color:#52606d;display:inline-flex;font-weight:850;justify-content:center;margin:0 2px;min-height:42px;min-width:132px;padding:7px 12px;vertical-align:middle}.drop-blank.is-correct{background:#dff5e5;border-color:#51ad6c;color:#17652f}.drop-blank.is-wrong{background:#ffe3e1;border-color:#d95c55;color:#9d2823}.passage-title{color:#303846;font-size:1.05rem;margin:16px 0 8px}.mistake-page-grid{display:grid;gap:12px;grid-template-columns:repeat(2,minmax(0,1fr))}.mistake-card{background:#fff7f6;border:1px solid #f0c4c0;border-radius:8px;padding:12px}.mistake-card span{color:#a4423d;display:block;font-size:.78rem;font-weight:900;margin-bottom:6px}.mistake-card strong{display:block;line-height:1.3;margin-bottom:8px}.mistake-card p,.empty-copy{color:#596575;line-height:1.4;margin-bottom:4px}.empty-state{align-content:center;background:#f8fafc;border:1px dashed #cdd7e1;border-radius:8px;display:grid;min-height:280px;padding:24px;text-align:center}.empty-state h3{font-size:clamp(1.4rem,3vw,2.2rem);margin:0}@media(max-width:1180px){.workspace{grid-template-columns:150px minmax(0,1fr)}}@media(max-width:900px){.app-shell{padding:12px}.topbar{align-items:flex-start;flex-direction:column;position:static}.workspace{grid-template-columns:1fr}.side-nav{display:flex;flex-wrap:wrap;position:static}.side-nav button{flex:1 1 150px}.pretest-row,.word-card-grid,.chapter-grid,.mistake-page-grid{grid-template-columns:1fr}.section-header{align-items:start;flex-direction:column}}@media(max-width:640px){.segmented-options,.card-options,.drop-row{grid-template-columns:1fr}.topbar-actions{align-items:stretch;width:100%}.ghost-button{flex:1}}